Radio frequency filter device

ABSTRACT

An electrical connector utilizing a pin assembly wherein the pin is coated with a dielectric and has a radio frequency energy absorbing sleeve around the dielectric and which is held in place by a solder coating. At the outer end of the radio frequency energy absorbing sleeve the pin grouping is adapted to receive an RF shield.

United States Patent Miertschin et al.

[451 May 16, 1972 RADIO FREQUENCY FILTER DEVICE Inventors: Jerrold L.Miertschin, Arlington, Tex.;

David H. Butler, Grafton, Va.

Assignee: The United States of America as represented by theAdministrator of the National Aeronautics and Space AdministrationFiled: May 28, 1970 Appl. No.: 41,347

US. Cl. ..339/143 R, 333/79, 339/147 R Int. Cl ..IIOIr 13/66 Field ofSearch ..333/79; 339/143, 147,154,

References Cited UNITED STATES PATENTS 3/1969 Rcinkc ct ul .333/792,892,173 6/1959 Brereton ..339/89 M 2,443,109 6/1948 Linder ..333/793,539,973 11/1970 Antes et a] ..339/143 3,002,162 9/ l 961 Garstang..333/79 3,582,862 6/1971 Anderson ..339/147 R Primary ExaminerMarvin A.Champion Assistant Examiner-Lawrence J. Staab Att0rney-Howard .1. Osbornand John R. Manning [5 7] ABSTRACT An electrical connector utilizing apin assembly wherein the pin is coated with a dielectric and has a radiofrequency energy absorbing sleeve around the dielectric and which isheld in place by a solder coating. At the outer end of the radiofrequency energy absorbing sleeve the pin grouping is adapted to receivean RF shield.

1 Claims, 2 Drawing Figures Patented May 16, 1972 2 Sheets-Sheet 1INVENTORS JERROLD L. MIERTSCHIN DAVID H. BUTLER ATTORNEY Patented May16, 1972 2 Sheets-Sheet 2 I 0 co 1- N m g o w uo l 1 n; In II II N Ill:I II w w 0 w 00' s N INVENTORS JERROLD L. MIERTSCHIN DAVID H. BUTLERATTORNEY- RADIO FREQUENCY FILTER DEVICE ORIGIN OF THE DISCLOSURE .usedby or for the Government for'governmental purposes without the paymentof any royalties thereon or therefor.

BACKGROUND OF THE INVENTION This invention relates generally to anelectrical connector and more particularly to a radio frequency (RF)interference shield for use in systems or components which would requiresuch interference to be blocked out.

The prior art is replete with various devices utilized for blocking orpreventing radio frequency interference from entering into an area ofcomponent which of necessity must be isolated from such radio frequencyinterference. Generally, these devices are quite large and ofinsufficient reliability for the high technological requirements of thespace age. The reliability of the previously known devices was reducedsubstantially by having to utilize numerous componentssolder joints andcomplicated construction procedures. Furthermore, these previously knowndevices had greater space requirements in view of their need to haveenlarged parts and additional components that required extra space inthe connections.

To overcome the many difficulties of the prior art, the use of a pinassembly having substantial RF interference reduction characteristicsthat is combined with an RF interference shield to provide aconventional connector device.

lt is an object of the instant invention to provide a reliable andcompact electrical connector providing radio frequency interferenceshielding characteristics.

A further object of the instant invention is to provide a radiofrequency interference shield device having increased reliabilityaccomplished by decreasing the total number of components, eliminationof solder joints and fewer operation in the manufacturing process.

A still further object of the instant invention is to provide a compactRF interference shield in a connector by utilizing the available spacein a connector shell to house the filters to eliminate the use of an RFcap and shielding of the cable between the connector and the cap.

Another object of this invention is to provide a connector pin assemblyhaving radio frequency interference shielding characteristics bycovering the connector pin with a dielectric surrounded by a sleeve of aradio frequency absorbing material and against which an RF interferenceshield can be abutted upon connection of the connector components.

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily apparent as the same becomes betterunderstood by reference to the following description when considered inconnection with the accompanying drawings wherein:

FIG. 1 shows an overall sectional view of the instant invention; and

- FIG. 2 shows a sectional view of a conventional connector modified inaccordance with the invention.

Referring now to the drawings, and particularly to FIG. 1, conventionalconnector 10 is shown to include a housing or element 12 having lockmember or lock ring 14 fitting thereabout for assistance in insuring arigid connection between the components of connector 10. Cable clamp 16fits to housing 12 and maintains cables 36 in their proper location.Connector housing 12 has insulated support 18 generally made of rubberor a potting compound for accurately retaining pin assemblies 20.

Filter pin assembly 20 includes pin 22 which is the portion of thefilter pin assembly that mates with the mating receptacle that isattached in an integral manner to pin 24 to be utilized in theconnection. Pin 24 has dielectric covering 26 completely surrounding andinsulating pin 24.

Radio frequency energy absorbing sleeve 28 fits around the centralportion of pin 24 and incases a portion of dielectric covering 26centrally of pin 24. Metallic radio frequency shielding materialprovides coating 30 for incasing sleeve 28 as well as dielectriccovering 26. Base 32, which is a portion of metallic radio frequencyshielding material 30, surrounds the outer end of pin 24 and dielectriccoating 26, to provide an accurate abutment for RF interference shield40. RF shield 40 would be made of a metallic material and provided withaccurately positioned openings 42 corresponding to the location and sizeof pin basses 32. Any number of pins 24, with their corresponding bases32 for receiving shield 40, can be utilized and it is a matter of designand utility as to the number of pins included in connector 10.

Socket 34 is an integral part of pin 24 and wire 36 is soldered tosocket 34.

Referring now to FIG. 2, a housing or adaptor 50 is shown connecting themale and female sections of connector 100 and the cable clamp 112.Adaptor 50 is generally cylindrical in configuration with exteriorthreads 52 at one end and and interior threads 54 at the opposite end.Internal flange 56 provides shoulder 58 for abutment of RF shield 60which supports filter assembly 62. 1 Filter assembly 62 includes pins 64which extend between socket 134 and wire 124 to provide an uninterruptedconductor element. Socket 74 may be utilized on the'end of pin 64adjacent wire 124 to insure a complete connection. It is to beunderstood also that pin 64 may be rigidly connected to socket 134 andwire 124 rigidly connected to socket 74 by solder 78, or similaradhesion.

Filter assembly 62 is substantially the same as filter assembly 20 inthat pin 64 is insulated by dielectric covering 66. A radio frequencyenergy absorbing sleeve 68 incases covering 66 and pin 64. Aconventional metallic radio frequency shielding material providescoating 70 about pin 64, dielectric covering 66 and cable clamp element112 has wires 124, covered by insulation 122, for mating with socket 134for receiving pins 64. Insulative support is made of rubber or similarinsulating material with a respective number of openings 82 forreceiving sockets 74 and wire 124 for proper assembly of connector 100.The assembly is accomplished by cable clamps 112 and 116 to adaptor 50by threads 52 and 54.

Thus it is seen that the instant invention provides a versatileelectrical connector that is simple and compact and is manufactured insuch a manner that the number of components if reduced to therebysubstantially increase and enhance the reliability of the connector. Thecompactness of the instant invention is realized because of the use ofthe available space in conventional connector shells for housing thefilter components. Furthermore, a great number of components andelements are eliminated to thereby enhance the reliability andcompactness of the instant invention with regard to other shieldingsystems. It is readily apparent that conventional connectors can beutilized with only a slight modification by inserting filter pinassembly 20, including RF shield 40. The concept can be incorporatedinto almost any type of connector with the same minimal modifications.The modifications do not detract from the original manufacturingspecifications of the connector in any way and permit the sealingproperties to be retained, which is an important feature relative toouter space and aircraft applications of the instant invention.Accordingly, it is to be understood that this concept can be applied toproduction of special connectors or for an adaptor for existingconnectors.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. An adapter for fitting between a pair of connectors, which is usedfor eliminating RF interference in at least one conductor, theconnectors having electrically conductive housings surrounding said atleast one conductor with the housings having male and female threads toaid in making a connection comprising:

an electrically conductive adapter housing with male threads on one ofits ends and with female threads on its other end for mating with thethreads on said connectors;

which said plate abuts and makes electrical contact with said adapterhousing; and

insulative support material substantially surrounding said filter meanson opposite sides of said plate whereby the ends of said filter meanscan be connected to the conductor ends to connect the adapter in theconductor circuits and with the plate forming an RF shield.

1. An adapter for fitting between a pair of connectors, which is usedfor eliminating RF interference in at least one conductor, theconnectors having electrically conductive housings surrounding said atleast one conductor with the housings having male and female threads toaid in making a connection comprising: an electrically conductiveadapter housing with male threads on one of its ends and with femalethreads on its other end for mating with the threads on said connectors;filter means having outer conductors for making electrical contact withsaid adapter housing for providing an RF interference shield; a rigidconductive plate with a hole therethrough for each of said filter meanssupporting said filter means, the size of each hole being such that theouter conductor of the filter means makes electrical contact with saidplate; a shoulder around the inside of said adapter housing againstwhich said plate abuts and makes electrical contact with said adapterhousing; and insulative support material substantially surrounding saidfilter means on opposite sides of said plate whereby the ends of saidfilter means can be connected to the conductor ends to connect theadapter in the conductor circuits and with the plate forming an RFshield.